Adaptive D-based Active Power Line Filter for Industrial and Commercial Power Distribution

Harmonic disturbances caused by non-linear loads such as power switching devices often occur in the industrial and commercial power distribution systems and can damage sensitive equipment connected to the systems, causing tremendous productivity loss. This paper presents a novel adaptive-harmonic- detection active filter, consisting of an industry-type power electronic inverter controlled by state-of-the-art digital signal processor (DSP). This adaptive-detection DSP-based (adaptive D-based) filter provides effective elimination of power-line disturbances due to its efficient adaptive harmonic detection algorithm implemented with a fast response DSP control for various power-line conditions. The algorithm is based on a novel noise cancellation theory, originally not designed for power applications. This paper presents a practical formulation of the algorithm for utility applications that significantly simplifies the complex formulation originally for noise cancellations. Hardware and software implementations of this adaptive D-based filter are detailed. Simulation and experimental results are provided to demonstrate the effectiveness of this filter.